In the wilder, open uplands of the North Bay, mountain lions remain a steady, if elusive presence. But just how many are out there? A current study of the big cats is trying to find that out, and learn much more about them.

That plume of smoke rising from the Bouverie Preserve near Glen Ellen late Tuesday morning was a carefully watched experiment in applying a land management technique that goes back thousands of years.

The fire took about three hours to burn across the designated 17 acre area. That was ample time for any affected wildlife to leave the area or take cover underground, says ACR Fire Ecologist Sasha Berleman, while deer, when they return, will find a more hospitable landscape.